It is estimated that more than half a million bone grafting procedures are performed in the United States annually with a cost over $2.5 billion. These numbers are expected to double by 2020. Both natural bone and bone substitutes have been used as graft materials. Natural bone may be autograft or allograft. Bone substitutes include natural or synthetic materials such as collagen, silicone, acrylics, calcium phosphate, calcium sulfate, or the like.
There are at least three ways in which a bone graft can help repair a defect. The first is osteogenesis, the formation of new bone within the graft by the presence of bone-forming cells called osteoprogenitor cells. The second is osteoinduction, a process in which molecules contained within the graft (e.g., bone morphogenic proteins and other growth factors) convert progenitor cells into bone-forming cells. The third is osteoconduction, a physical effect by which a matrix often containing graft material acts as a scaffold on which bone and cells in the recipient are able to form. The scaffolds promote the migration, proliferation and differentiation of bone cells for bone regeneration.
Demineralized bone matrix (DBM) has been shown to exhibit the ability to induce and/or conduct the formation of bone. It is therefore desirable to implant and maintain demineralized bone matrix at a site which bone growth is desired.
Bone fiber based-demineralized bone matrices for implantation exhibit improvements in mechanical properties, including cohesiveness, fiber length, fiber diameter or width, fiber aspect ratio, or a combination of multiple variables.
Oftentimes, when DBM fibers are made they lack cohesiveness and tend to fall apart or become loose in the package or during processing. In order to reduce this tendency, a binder (e.g., glycerol) is commonly added to keep the DBM fibers together. The inclusion of a binder can lead to additional manufacturing expenses and further complicate regulatory approval processes.
Therefore, there is a need for DBM compositions, devices and methods that allow osteogenesis, osteoinduction and/or osteoconduction. DBM compositions, devices and methods that can be made from bone material that does not need a binder would be beneficial. Furthermore, DBM compositions, devices and methods that easily allow hydration of the demineralized bone matrix would be beneficial.